Hardiness zone 6a · 272 stations

Zone 6a Frost Dates: Typical Last Frost Apr 30

Summary across 272 NOAA weather stations whose location falls in zone 6a^*. Dates are the typical (50% chance) frost dates of each station; the table shows the spread between stations.

Typical last frostApril 30median station, 50% chance
Typical first fall frostOctober 15median station, 50% chance
Frost-free season168 daysmedian station
Weather stations272dates differ by weeks inside a zone

Typical (50%) frost dates across stations in zone 6a
	25% of stations	Median station	75% of stations
Last frost in spring (32°F)	April 22	April 30	May 6
First frost in fall (32°F)	October 9	October 15	October 20
Frost-free days	156	168	179

Frost dates inside one zone differ by weeks: the zone describes winter cold, not the length of the season. Use the station closest to you.

Stations in zone 6a

Weather stations with their typical (50% chance) frost dates
Station	Zone	Last spring frost (50%)	First fall frost (50%)	Frost-free days
Adrian, MI	6a	May 1	October 15	164
Albany, NY	6a	April 27	October 15	169
Alpena, MI	6a	May 5	October 17	163
Alta, UT	6a	June 11	September 18	98
Altenbern, CO	6a	May 25	September 25	120
Amherst, MA	6a	May 5	October 8	156
Amity, MO	6a	April 19	October 19	180
Anderson, IN	6a	April 19	October 23	186
Angola, IN	6a	April 30	October 16	167
Ann Arbor, MI	6a	May 3	October 13	160
Atwood, KS	6a	May 2	October 8	157
Augustine, NM	6a	May 19	October 4	137
Avon, NY	6a	May 3	October 15	163
Bad Axe, MI	6a	May 5	October 19	163
Baker City, OR	6a	May 25	September 15	111
Bakersville, CT	6a	May 8	October 5	151
Barnes Station, OR	6a	June 2	September 17	104
Bartow, WV	6a	May 9	October 5	149
Batavia, NY	6a	May 3	October 16	165
Bellefontaine, OH	6a	April 26	October 20	175
Belleville, KS	6a	April 22	October 17	175
Bentley, IL	6a	April 13	October 22	191
Berne, IN	6a	April 23	October 22	181
Bethany, MO	6a	April 16	October 22	186
Binghamton, NY	6a	May 2	October 11	162
Bluffton, IN	6a	April 24	October 20	179
Bonny Dam 2 NE, CO	6a	May 5	October 10	155
Boulder, CO	6a	May 6	October 5	151
Boundary Dam, WA	6a	May 4	October 4	153
Bucyrus, OH	6a	April 19	October 27	190
Burlington, CO	6a	May 6	October 9	155
Burlington (Airport), IA	6a	April 15	October 20	187
Cambridge, ID	6a	May 15	September 27	134
Canon City, CO	6a	May 4	October 7	153
Canton, PA	6a	May 16	October 2	139
Celina, OH	6a	April 27	October 19	175
Centerburg, OH	6a	April 27	October 17	172
Champaign, IL	6a	April 15	October 24	190
Chardon, OH	6a	May 5	October 18	164
Charleston, IL	6a	April 15	October 23	187
Charlotte, MI	6a	May 1	October 15	164
Chewelah, WA	6a	May 16	September 15	120
Chicago (O'Hare Airport), IL	6a	April 16	October 28	193
Chicago Botanic Garden, IL	6a	April 26	October 21	176
Chillicothe, MO	6a	April 15	October 21	187
Cimarron, NM	6a	May 11	October 3	143
Clay Center, NE	6a	April 19	October 20	181
Colby, KS	6a	May 2	October 9	156
Colorado Springs, CO	6a	May 3	October 8	158
Columbia City, IN	6a	April 27	October 17	171
Conception, MO	6a	April 17	October 20	184
Cortez, CO	6a	May 12	October 7	147
Crete, NE	6a	April 23	October 12	170
Dansville, NY	6a	May 4	October 16	163
Danville, IL	6a	April 21	October 20	181
Dayton, OH	6a	April 16	October 28	194
Defiance, OH	6a	April 22	October 24	183
Deseret, UT	6a	May 14	September 30	137
Dorset, OH	6a	May 10	October 10	154
Dowagiac, MI	6a	May 4	October 11	158
Dubois, PA	6a	May 6	October 14	160
Duchesne, UT	6a	May 6	October 5	150
Durham, NH	6a	May 8	October 4	148
Eads, CO	6a	April 30	October 13	165
East Tawas, MI	6a	May 8	October 5	148
Eaton, OH	6a	April 25	October 20	176
Ebensburg, PA	6a	May 17	October 2	136
Elkins, WV	6a	May 5	October 12	159
Elmira, NY	6a	May 6	October 11	158
Ephraim, UT	6a	May 28	September 20	113
Epping, NH	6a	May 7	October 4	148
Fairbury, NE	6a	April 25	October 15	169
Farmland, IN	6a	April 25	October 16	173
Fort Madison, IA	6a	April 12	October 25	194
Fort Wayne, IN	6a	April 24	October 21	178
Garrett, IN	6a	May 2	October 10	159
Geneva, NE	6a	April 20	October 18	178
Goodland, KS	6a	May 2	October 11	158
Goshen, IN	6a	April 26	October 21	175
Grand Rapids, MI	6a	April 29	October 20	174
Great Sand Dunes National Park & Preserve, CO	6a	May 21	October 1	131
Greenland, NH	6a	May 4	October 8	157
Greenville, OH	6a	April 21	October 20	180
Halfway, OR	6a	May 15	September 24	130
Hannibal, MO	6a	April 10	October 27	199
Hartford City, IN	6a	April 22	October 22	181
Hastings, MI	6a	May 3	October 12	158
Hastings, NE	6a	April 25	October 14	171
Hawley, PA	6a	May 10	October 4	146
Hayes Center, NE	6a	May 3	October 10	159
Healy, KS	6a	April 28	October 15	169
Hebron, NE	6a	April 24	October 15	172
Hemlock, NY	6a	May 2	October 18	167
Herington, KS	6a	April 24	October 14	173
Hillsdale, MI	6a	May 3	October 12	161
Hiram, OH	6a	May 1	October 20	170
Holdrege, NE	6a	May 2	October 11	162
Honeoye, NY	6a	May 10	October 4	147
Hoopeston, IL	6a	April 22	October 19	180
Horton, KS	6a	April 18	October 17	180
Huntington, IN	6a	May 1	October 14	166
Imlay, NV	6a	May 17	September 27	131
Indiana Dunes NL, IN	6a	April 22	October 27	188
Indianapolis, IN	6a	April 15	October 26	193
Jacksonville, IL	6a	April 19	October 17	179
Jamestown, NY	6a	May 8	October 13	158
Jamestown, PA	6a	May 4	October 14	161
Kennebunkport, ME	6a	May 9	October 3	146
Kenosha, WI	6a	April 19	October 26	189
Kim 15 NNE, CO	6a	May 5	October 9	156
Kingsley Dam, NE	6a	April 22	October 18	176
Kirksville, MO	6a	April 21	October 19	179
Kokomo, IN	6a	April 27	October 18	174
La Junta, CO	6a	April 24	October 15	173
Lafayette, IN	6a	April 20	October 20	182
Lafayette (Purdue University Airport), IN	6a	April 26	October 18	173
Lakeville, IN	6a	May 1	October 13	163
Lamar, CO	6a	April 30	October 10	163
Laporte, IN	6a	April 19	October 27	191
Las Animas, CO	6a	April 29	October 12	166
Libby Dam (Base), MT	6a	May 11	October 1	142
Lincoln, IL	6a	April 20	October 16	179
Lincoln, NE	6a	April 24	October 13	171
Linesville, PA	6a	April 30	October 23	177
Logan Radio Kvnu, UT	6a	May 8	October 2	145
Manti, UT	6a	May 11	October 6	146
Marion, IN	6a	April 26	October 20	175
Marion, OH	6a	April 25	October 20	178
Marlinton, WV	6a	May 11	October 6	148
Marquette (USW00014838), MI	6a	May 8	October 21	164
Martinsville, IN	6a	April 24	October 15	173
Marysville, KS	6a	April 25	October 13	171
McGill, NV	6a	May 28	September 24	119
Midland, MI	6a	April 29	October 16	167
Millersburg, OH	6a	May 2	October 14	164
Minidoka Dam, ID	6a	May 16	October 1	136
Montague, MI	6a	May 19	October 4	136
Mount Leconte, TN	6a	May 22	October 1	132
Mount Mitchell, NC	6a	May 16	October 4	140
Nashua, NH	6a	April 30	October 12	165
Nebraska City, NE	6a	April 18	October 19	182
Neola, UT	6a	May 19	September 29	130
New Castle, IN	6a	April 27	October 17	173
New Lexington, OH	6a	April 30	October 17	168
Newark, OH	6a	April 29	October 16	167
Newcastle, ME	6a	April 27	October 18	172
Norfolk, CT	6a	May 3	October 11	161
Normal, IL	6a	April 25	October 16	172
Northglenn, CO	6a	May 2	October 11	160
Norton, KS	6a	April 27	October 17	173
Norton Dam, KS	6a	May 1	October 12	162
Oakland, MD	6a	May 6	October 9	156
Oakley, KS	6a	May 6	October 9	156
Oregon, MO	6a	April 16	October 20	186
Orovada, NV	6a	June 2	September 11	102
Ottawa, IL	6a	April 20	October 22	183
Owosso, MI	6a	May 1	October 15	164
Pandora, OH	6a	April 23	October 22	180
Park Forest, IL	6a	April 23	October 20	179
Parsons, WV	6a	April 24	October 24	182
Partoun, UT	6a	May 13	September 29	137
Paul, ID	6a	May 6	October 6	151
Peoria, IL	6a	April 16	October 23	189
Perrysville, IN	6a	April 23	October 14	171
Plymouth, IN	6a	April 25	October 21	178
Pocatello (Airport), ID	6a	May 23	September 18	117
Pontiac, IL	6a	April 16	October 24	191
Portland, ME	6a	April 26	October 15	170
Preston, ID	6a	May 16	September 28	133
Priest River, ID	6a	May 20	September 13	114
Quincy, IL	6a	April 14	October 23	191
Quincy Dam 21, IL	6a	April 8	October 30	204
Quinter, KS	6a	April 24	October 18	176
Racine, WI	6a	April 20	October 24	184
Ramsey, IL	6a	April 15	October 19	185
Rantoul, IL	6a	April 21	October 18	179
Renovo, PA	6a	April 30	October 22	173
Rensselaer, IN	6a	April 23	October 18	177
Republic, WA	6a	May 30	September 10	102
Richfield, ID	6a	May 24	September 26	123
Richmond, UT	6a	May 11	October 5	143
Ridgway, PA	6a	May 13	October 11	150
Rochester, IN	6a	April 23	October 21	180
Rosebud, MO	6a	April 27	October 13	168
Rushville, IN	6a	April 19	October 23	185
Saint Francis, KS	6a	April 30	October 10	160
Salisbury, MO	6a	April 12	October 22	190
Scott City, KS	6a	April 30	October 15	167
Sharon Springs, KS	6a	April 28	October 15	168
Sheep Mountain, CO	6a	May 27	September 25	119
Shelbina, MO	6a	April 21	October 17	177
Sidney, IA	6a	April 19	October 19	182
Sidney, OH	6a	April 27	October 20	175
Slippery Rock, PA	6a	May 7	October 14	158
Smith Center, KS	6a	April 24	October 15	173
Spencer, IN	6a	April 20	October 20	180
Spickard, MO	6a	April 20	October 16	177
Springerville, AZ	6a	June 1	September 26	114
Springfield, OH	6a	April 25	October 19	175
St. James 4 SSW Beaver, MI	6a	May 11	October 19	159
Steffenville, MO	6a	April 17	October 19	184
Stevenson Dam, PA	6a	May 10	October 16	157
Superior, NE	6a	April 29	October 10	162
Tenants Harbor, ME	6a	April 27	October 25	178
Three Rivers, MI	6a	April 30	October 17	170
Tipton, IN	6a	April 23	October 17	174
Titusville, PA	6a	May 12	October 10	149
Tribune, KS	6a	May 2	October 11	160
Troy, KS	6a	April 19	October 19	182
Tuscola, IL	6a	April 15	October 20	188
Urbana, OH	6a	April 24	October 19	179
Wales, NY	6a	May 7	October 10	155
Walsenburg, CO	6a	May 6	October 4	149
Warren, OH	6a	May 8	October 12	157
Warren, PA	6a	May 4	October 21	168
Warsaw, NY	6a	May 7	October 10	156
Washington, KS	6a	April 24	October 14	171
Washington Island, WI	6a	May 15	October 14	152
Wauseon, OH	6a	April 29	October 16	170
West Lafayette, IN	6a	April 26	October 12	169
Wheat Ridge, CO	6a	May 5	October 5	151
White Hall, IL	6a	April 13	October 22	190
Whitestown, IN	6a	April 21	October 20	180
Winamac, IN	6a	April 25	October 18	173
Winnemucca, NV	6a	May 31	September 17	108
Wooster, OH	6a	April 30	October 12	163
Worthington, MA	6a	May 13	October 2	144
Zuni, NM	6a	May 29	October 2	127
near Aurora, CO	6a	May 4	October 8	156
near Burlington, IA	6a	April 18	October 20	185
near Canton, MO	6a	April 11	October 23	194
near Chicago, IL	6a	April 10	November 1	203
near Coldwater, MI	6a	May 2	October 13	163
near Falls City, NE	6a	April 18	October 17	180
near Fiskdale, MA	6a	April 28	October 15	169
near Flagstaff, AZ	6a	June 4	September 28	115
near Frankfort, IN	6a	April 21	October 21	181
near Franklin, NE	6a	April 30	October 8	161
near Garden City, KS	6a	April 28	October 17	171
near Garland, UT	6a	May 3	October 12	160
near Jackson, MI	6a	May 1	October 14	164
near Jasonville, IN	6a	April 14	October 26	193
near Joliet, IL	6a	April 19	October 25	188
near Keokuk, IA	6a	April 10	October 27	198
near Lansing, MI	6a	May 1	October 13	162
near Logan, UT	6a	April 30	October 16	166
near Logansport, IN	6a	April 20	October 23	185
near Macon, MO	6a	April 8	October 28	201
near Manchester, NH	6a	April 30	October 11	164
near Manhattan, KS	6a	April 22	October 20	179
near Mansfield, OH	6a	April 26	October 22	177
near Midway, UT	6a	May 28	September 23	119
near Milwaukee, WI	6a	April 19	October 29	192
near Ogden, UT	6a	May 22	September 26	125
near Oquawka, IL	6a	April 8	October 29	202
near Paris, IL	6a	April 21	October 20	179
near Patton, PA	6a	May 10	October 5	149
near Richfield, UT	6a	May 21	September 24	125
near Saginaw, MI	6a	April 26	October 17	172
near South Bend, IN	6a	May 1	October 19	170
near Springfield, IL	6a	April 14	October 20	187
near Syracuse, NY	6a	April 29	October 19	173
near Traverse City, MI	6a	May 12	October 16	155
near Trenton, NE	6a	April 29	October 13	166
near Trinidad, CO	6a	May 4	October 9	156
near Troy, NY	6a	April 19	October 26	190
near Union Springs, NY	6a	May 1	October 21	172

Sources

* zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.